The son of a British woman who has been held in Iran since January on espionage charges along with her husband has called on the UK government to raise their case during talks with Iran reportedly taking place in Istanbul later this week.

Lindsay and Craig Foreman, both 52, were arrested on 3 January in Kerman, southern Iran, while travelling through the country from Armenia to Pakistan on a motorcycle journey to Australia.

The family, who have not had direct contact with the couple since their incarceration, have said promises from the Foreign Office in the past fortnight to arrange conversations with the couple had not materialised.

Six weeks ago, the Foreign Office said it did not know the couple’s whereabouts, despite initially having said they were being transferred to Evin prison in Tehran.

Lindsay’s eldest son, Joe Bennett, said the family were past breaking point. “The silence is intolerable, inhumane and a stain on the duty of care that the British government owes its citizens.”

“While other countries are ensuring their citizens’ cases are raised at the highest levels in negotiations with Iran, we are left shouting into the void, writing letters, running social media campaigns, tagging David Lammy and Keir Starmer and hearing nothing. We are losing faith,” said Bennett, 31.

After Israel’s bombing of Tehran’s Evin prison on 23 June that left more than 70 dead, the family said they “endured unimaginable fear”, uncertain of the couple’s wellbeing. Yesterday, the family said they learned the couple was moved from Kerman to a location in Tehran, but said the British government had not confirmed their safety or wellbeing.

The Foreign Office has been approached for comment.

Renewed calls for their release come after nearly two weeks of war between Israel and Iran in June, during which the US bombed a number of Iran’s nuclear sites and brought nuclear talks to an abrupt end.

As Iran maintains a fragile ceasefire with the US and Israel, the family has called on the UK government to table the couple’s case after learning negotiations between the UK and Iran were set to take place in Istanbul later this week.

The UK, France and Germany – the E3, which signed the original nuclear deal with Iran in 2015 – reportedly met Iranian officials for nuclear talks in Istanbul last week, after threatening to reimpose “snapback” UN sanctions without the risk of a security council veto, so long as they act by its expiry in October.

The 2015 deal does not allow other signatories, China or Russia, to veto the sanctions snapback, and since leaving the deal in 2018, the US cannot veto the UK or EU move.

The family have also called for immediate public commitment from Lammy and Starmer, as well as to prioritise urgent and regular phone calls, consular visits and medical and legal support. It is understood the British couple have been visited by consular officials three times, the most recent in May, and have had no medical or consular visits for more than 75 days.

“We cannot and will not remain silent while our loved ones are left to disappear into the shadows of bureaucracy and apathy,” said Bennett. “This is no longer just a diplomatic issue. It is a humanitarian emergency. The government must act now, before it’s too late.”

Bennett said it was difficult hearing accounts from former detainees and not knowing the conditions in which his mother and her husband were being held, or whether they were still being held together.

“I need to speak to my mum,” said Bennett. He described the ordeal as torturous for himself and the family. “It’s hard for me to say with 100% confidence that I know my mum’s alive, and it’s mental to even think to say that, but that is the reality, I haven’t spoken to my mum.”

While drawing positivity from continuous setbacks was hard, said Bennett, two messages he had sent to his mother kept him grounded: that he was always looking for and at the moon, and thinking of embracing the couple on their safe return.

“We’re starting to feel like we’re not being heard, there’s no recognition or acknowledgment of what we’re doing by the powers that be that can make a difference,” he added. “It’s like we’re screaming into the void at the moment.”

On 23 July, the all-party parliamentary group (APPG) for arbitrary detention and hostage affairs wrote to the UK foreign secretary, urging the government to prioritise their case and take further steps to secure their release.

The group’s chair, Alicia Kearns, who wrote to Lammy along with other MPs, told the Guardian on Wednesday that the government could not take part in negotiations with Iran without the couple’s release. The MP added that the detention of other British nationals in Iran such as Mehran Raoof was one of the central issues to negotiate.

“This cannot be an afterthought while their lives are at risk. President [Emmanuel] Macron has publicly and strongly called for the release of the French nationals held hostage in Iran. It is deplorable that Keir Starmer and David Lammy have the opportunity to negotiate their release, and are not doing everything they can to take it,” said Kearns.

A Foreign Office spokesperson said: “We are deeply concerned by reports that two British nationals have been charged with espionage in Iran. We continue to raise this case directly with the Iranian authorities.

“We are providing them with consular assistance and remain in close contact with their family members.”

• This article was amended on 31 July 2025 to correct the spelling of the Iranian city of Kerman.